This project describes the formulation activities in the intramural laboratory with drugs of interest to the Division of Cancer Treatment, NCI. Primarily, these studies are directed toward evaluation of the stability of certain new antitumor agents and resolution of solubility problems presented by these substances. Echinomycin, Spirohydantoin Mustard, Aziridinylbenzoquinone and NSC-127755, a Baker type antifol are representative examples. The above substances were rendered soluble by a mixed solvent approach using ethanol or dimethylacetamide plus a surfactant or emulsion system. Stability indicating high performance liquid or gas chromatographic systems were developed and used to monitor degradation. Formulation studies were not restricted to antineoplastic agents and included work on delta-9-THC, an antiemetic, and morphine related analgesics.